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锁磷剂与增氧剂联用去除沉积物中砷的效果与机制

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水资源保护 2024年第3期40卷 149-156页

作者：燕文明李皋翔陈红颜秉龙陈翔何翔宇李琪傅聪玮邵一纯河海大学水灾害防御全国重点实验室江苏南京210098 河海大学水科学研究院江苏南京210098 连云港市水利规划设计院有限公司江苏连云港222006 生态环境部南京环境科学研究所江苏南京210008

为研究锁磷剂(LMB)与增氧剂CaO_(2)联合应用对富营养化湖泊沉积物中砷(As)污染的去除效果,理清联用技术对沉积物水界面As的去除机制,以太湖梅梁湾底泥为研究对象开展模拟试验。结果表明:LMB与CaO_(2)联用对沉积物中的As的去除效果优于LM... 详细信息

为研究锁磷剂(LMB)与增氧剂CaO_(2)联合应用对富营养化湖泊沉积物中砷(As)污染的去除效果,理清联用技术对沉积物水界面As的去除机制,以太湖梅梁湾底泥为研究对象开展模拟试验。结果表明:LMB与CaO_(2)联用对沉积物中的As的去除效果优于LMB、CaO_(2)单独使用;在试验第45天,LMB与CaO_(2)联用对沉积物溶解态As去除率最大,为39.31%,在试验第90天,LMB与CaO_(2)联用对As的去除效果较差;为实现沉积物中As的高效去除,可在加入LMB和CaO_(2)45 d后对LMB和CaO_(2)进行回收;LMB与CaO_(2)联用去除As的主要机制为LMB和CaO_(2)中的La^(3+)、Ca^(2+)与砷酸根离子络合形成LaAsO_(4)和Ca_(3)(AsO_(4))2沉淀以及Fe(Ⅲ)、Mn(Ⅳ)氧化物的协同吸附作用;Fe和Mn氧化还原在控制沉积物As的释放中起着关键作用。

关键词：锁磷剂增氧剂砷协同吸附作用去除机制

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基于大型底栖动物功能摄食类群的太湖流域河流生态系统功能特征

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生态学杂志 2024年第4期43卷 982-992页

作者：燕文明姚琦蔡永久黎明杰高俊峰李宽意张又河海大学水灾害防御全国重点实验室南京210098 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室南京210008 中国科学院大学中丹学院北京100049

为了解功能摄食类群参数表征的生态系统功能特征,基于太湖流域河流73个样点的大型底栖动物和环境因子数据,分析了两大生态区生物多样性指数和功能摄食类群参数及其相关关系。结果表明,西部丘陵区生物多样性指数整体高于东部平原区。功... 详细信息

为了解功能摄食类群参数表征的生态系统功能特征,基于太湖流域河流73个样点的大型底栖动物和环境因子数据,分析了两大生态区生物多样性指数和功能摄食类群参数及其相关关系。结果表明,西部丘陵区生物多样性指数整体高于东部平原区。功能摄食类群参数与功能多样性指数的相关性更高,物质循环能力与功能均匀度指数和物种多样性指数呈显著负相关,物质纵向输送与功能丰富度指数和Rao二次熵指数呈显著正相关,沿岸物质输入量与物种多样性指数呈显著正相关。冗余分析筛选出对生物多样性指数影响较大的环境因子为溶解氧、总氮、硝态氮、底质指数和浊度,对功能摄食类群参数影响较大的是溶解氧和硝态氮。分段结构方程模型结果表明,营养盐浓度对生态系统功能产生直接负向效应,也可以通过生物多样性指数作用于生态系统功能而产生间接效应,而底质指数对生态系统功能产生直接正向效应,也可以通过生物多样性指数间接正向作用于生态系统功能。

关键词：功能多样性分类学多样性功能摄食类群冗余分析分段结构方程模型

Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan ZHAO Han yan Ge yan Ao CHEN wenming ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

Thermal noise-driven resonant sensors

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Microsystems & Nanoengineering 2024年第3期10卷 259-271页

作者： yan Qiao Alaaeldin Elhady Mohamed Arabi Eihab Abdel-Rahman wenming Zhang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Systems Design Engineering University of WaterlooWaterlooONCanada

MEMS/NEMS resonant sensors hold promise for minute mass and force ***,one major challenge is that conventional externally driven sensors inevitably encounter undesired intrinsic noise,which imposes a fundamental limitation upon their signal-to-noise ratio(SNR)and,consequently,the ***,this restriction becomes increasingly pronounced as sensors shrink to the *** this work,we propose a counterintuitive paradigm shift that turns intrinsic thermal noise from an impediment to a constituent of the sensor by harvesting it as the driving force,obviating the need for external actuation and realizing‘noise-driven’*** sensors employ the dynamically amplified response to thermal noise at resonances for stimulus *** demonstrate that lightly damped and highly compliant nano-structures with high aspect ratios are promising candidates for this class of *** overcome the phase incoherence of the drive force,three noise-enabled quantitative sensing mechanisms are *** validated our sensor paradigm by experimental demonstrating noise-driven pressure and temperature ***-driven sensors offer a new opportunity for delivering practical NEMS sensors that can function at room temperature and under ambient pressure,and a development that suggests a path to cheaper,simpler,and low-power-consumption sensors.

关键词： noise resonant overcome

Numerical simulation of water-slag elbow erosion-inhibiting by regulating the slag injection position with a novel preceding rotating sheet structure

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Particuology 2024年第7期90卷 323-339页

作者： Fopeng Wen Liuyun Xu Yixiang Chen Zhaofu Deng Shen Zhang wenming Song Yuge Li Liping Wei School of Chemical Engineering Northwest UniversityXi’an710069China School of Chemistry and Chemical Engineering Yan'an UniversityYan'an716000China Machinery Industry Shanghai Lanya Petrochemical Equipment Inspection Institute Co. Ltd.Shanghai201518China The Research Center of Chemical Engineering Applying Technology for Resource of Shaanxi Xi’an710069China

The elbow erosion seriously jeopardizes the safe and stable operation of water–slag discharge pipeline of the coal gasification *** work simulated water–slag elbow characteristics with various slag injection positions by simulating five simplified and representative erosion categories,including A-type horizontal-vertical elbow with an upstream flow,B-type horizontal-vertical elbow with a downstream flow,C-type vertical-horizontal elbow with an upstream flow,D-type vertical-horizontal elbow with a downstream flow and E-type horizontal-horizontal *** with the C/D-type elbow,where particles were injected uniformly,the A-type elbow and E-type elbow were found to increase erosion rate,while the B-type elbow decreases erosion *** interesting discovery is that the elbow erosion rate is relatively low for small particles when particles are injected from the middle and bottom positions of the inlet section of the *** on the observation,a novel preceding rotating sheet structure was developed to regulate the particle injection *** shows an excellent anti-erosion performance by reducing the maximum erosion rate of particles with diameters of 50,100,and 200μm by 23%,35%,and 43%,respectively.

关键词： Erosion Slag-water Uneven particles Elbow pipe Erosion inhibition Preceding rotating sheet structure

The Qitai radio telescope

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 150-161页

作者： Na Wang Qian Xu Jun Ma Zhiyong Liu Qi Liu Hailong Zhang Xin Pei Maozheng Chen Richard N.Manchester Kejia Lee Xingwu Zheng Hans J.Kärcher Wulin Zhao Hongwei Li Dongwei Li Martin Süss Matthias Reichert Zhongyi Zhu Congsi Wang Mingshuai Li Rui Li Ning Li Guljaina Kazezkhan wenming yan Gang Wu Lang Cui Ming Zhang Haitao Li Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China Australia Telescope National Facility CSIRO Space and AstronomyEpping 1710Australia Department of Astronomy Peking UniversityBejing 100871China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Dr.Hans Jirgen Karcher Engineering Office Karben 61184Germany Northwest China Research Institute of Electronic Equipment Xi'an 710065China OHB Digital Connect(MT Mechatronics) Mainz 55130Germany Beijing Institute of Architetural Design Beijing 100045China Guangzhou Instiute of Technology Xidian UniversityGuangzhou 510555 China

This study presents a general outline of the Qitai radio telescope(QTT)***,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 *** QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m *** QTT has adopted an umbrella support,homology-symmetric lightweight *** main reflector is active so that the deformation caused by gravity can be *** structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 *** satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be *** will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing *** compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system *** QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the *** QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing *** astrometric observations will also contribute to improving the accuracy of the celestial reference ***,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.

关键词： radio telescope radio astronomy observation receiver RFI

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锁磷剂和增氧剂对沉积物内源污染物钴的吸附

河海大学学报（自然科学版） 2022年第4期50卷 90-97页

作者：李敏娟燕文明陈翔何翔宇闫钰霖田玢河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学全球变化与水循环国际合作联合实验室江苏南京210098

为探究不同吸附材料(锁磷剂和增氧剂)对沉积物内源污染物Co的影响机制,以太湖梅梁湾为研究区域,设计3组室内模拟试验(对照组、增氧剂组及锁磷剂组),基于高分辨率平衡式间隙水采样(HR-Peeper)装置采集4个阶段(加入吸附材料后的第4天、30... 详细信息

为探究不同吸附材料(锁磷剂和增氧剂)对沉积物内源污染物Co的影响机制,以太湖梅梁湾为研究区域,设计3组室内模拟试验(对照组、增氧剂组及锁磷剂组),基于高分辨率平衡式间隙水采样(HR-Peeper)装置采集4个阶段(加入吸附材料后的第4天、30天、90天、150天)水样,解析原位覆盖条件下沉积物剖面溶解态Co、Fe(Ⅱ)、Mn的垂向分布特征及相互作用机制。结果表明:锁磷剂和增氧剂未造成水体中的pH值和Eh值的剧烈变化;沉积物剖面中溶解态Co质量浓度降低了1.29%~45.87%,且30 d时的吸附效果最好;增氧剂组及锁磷剂组沉积物-水界面Co释放通量较对照组分别降低了1.00μg/(m^(2)·d)和1.19μg/(m^(2)·d);沉积物剖面Co的释放受铁、锰的氧化还原控制,且主要受锰的氧化还原控制;增氧剂对钴的吸附效果优于锁磷剂,且有效吸附时间更久。

关键词：锁磷剂增氧剂沉积物溶解态Co 梅梁湾

Single-pulse Emission Variation of Two Pulsars Discovered by FAST

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Research in Astronomy and Astrophysics 2023年第7期23卷 96-109页

作者： Ziping Guo Zhigang Wen Jianping Yuan Feifei Kou Qingdong Wu Na Wang Weiwei Zhu Di Li Mengyao Xue Pei Wang Chenchen Miao De Zhao Yue Hu wenming yan Jiarui Niu Rukiye Rejep Zhipeng Huang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China National Time Service Center(NTSC)of the Chinese Academy of Sciences(CAS) Xi'an 710600China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Zhejiang Lab Hangzhou 311121China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

We investigate the single-pulse emission variations of two pulsars,PSRs J0211+4235 and J0553+4111,observed with the Five-hundred-meter Aperture Spherical radio Telescope at the 1.25 GHz central *** observation sessions span from 2020 December to 2021 July,with 21 and 22 observations for them *** integrated pulse profile of PSR J0211+4235 shows that there is a weak pulse component following the main component,and PSR J0553+4111 displays a bimodal profile with a bridge component in the *** J0211+4235 presents significant nulling phenomenon with nulling duration lasting from 2 to 115 pulses and burst duration lasting from 2 to 113 *** NF of each observation is determined to be 45%-55%.No emission greater than threeσis found in the mean integrated profile of all nulling *** most cases,the pulse energy changes abruptly during the transition from null to burst,while in the transition from burst to null there are two trends:abrupt and *** find that the nulling phenomenon of PSR J0211+4235 is periodic by the Fourier transform of the null and burst *** addition,the single-pulse modulation characteristics of these two pulsars are investigated,and the distributions of modulation index,LRFS and 2DFS are analyzed with *** left peak of PSR J0553+4111 has intensity ***,the polarization properties of these two pulsars are obtained through polarization calibration,and their characteristics are *** possible physical mechanisms of these phenomena are discussed.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR J0211+4235 PSR J0553+4111) stars:neutron

International standard of Traditional Chinese Medicine Techniques: Traditional Chinese Medicine guidelines for acute primary headache(2022)

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Journal of Traditional Chinese Medicine 2024年第4期44卷 839-850页

作者： YAO Yuning CAO Kegang ZHANG Genming LIU Jianping CHEN Wei CAO Junling yanG wenming yan Yongmei GENG Chang JU Yi ZHAO Dexi QU Miao LI Xiaoli SUN Li HAN Zhenyun HE Liyun CUI Fangyuan FU Caihong ZHOU Bo LIAO Shuqin Department of Geriatrics Jilin Academy of Traditional Chinese Medicine Department of Neurology Shenzhen Hospital of Beijing University of Chinese Medicine Institute of Basic Research in Clinical Medicine China Academy Of Chinese Medical Sciences Department of Rehabilitation Shunyi HospitalBeijing Traditional Chinese Medicine Hospital Department of Neurology Xiyuan Hospital of China Academy of Chinese Medical Sciences Department of Neurology Dongzhimen Hospital of Beijing University of Chinese Medicine Centre for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine Encephalopathy center First Affiliated Hospital of Anhui University of Chinese Medicine Department of Neurology Affiliated Hospital of Shaanxi University of Chinese Medicine Department of Neurology Beijing Changping District Hospital of Traditional Chinese Medicine Neurology center Beijing Tiantan HospitalCapital Medical University Department of Neurology Affiliated Hospital of Changchun University of Chinese Medicine Department of Neurology Xuanwu HospitalCapital Medical University Department of Neurology Beijing University of Chinese Medicine Third Affiliated Hospital

OBJECTIVE: To summarize the evidence from Traditional Chinese Medicine(TCM) practice in the treatment of acute primary headache and provide clinical practice guidance. METHODS: The guidelines were developed in accordance with the World Health Organization guideline development manual. After the establishment of steering committee, panel and the registration and protocol formulation, the evidence on TCM for acute primary headache from published guidelines, clinical evidence, and expert experience and consensus were collected. The grading of recommendations assessment, development and evaluation method was used to grade the evidence and make the recommendations. RESULTS: Based on the available evidence, the guidelines recommended three TCM herbal decoctions, six Chinese patent medicines, and two kinds of external application of Chinese herbal medicines. Diagnostic recommendations based on the expert experience and consensus were also included in the guidelines. CONCLUSION: TCM diagnosis and treatment of decoction, Chinese patent medicine and external application for treating acute primary headache were recommended. We hope these guidelines will be helpful in standardize the TCM acute treatment of primary headache.

关键词： acute primary headache medicine, Chinese traditional practice guideline